I have 2 Dell Dimension 9150 desktops that I've being using for trading for
10 years. They still run like new!!
I've been using a Fujitsu laptop every day for 8 years. Other than the fan being noisy it still runs fine.
I do a disk clean up, disk defrag, check disk, and virus scans etc. every week. Maybe that's why they've lasted so long.
Dell Precision has been their best line... both desktop and laptop.
Dell Dimension, originally their "middle" grade but now discontinued, has been very good too. The 1st one I had was sold to a neighbor, and he still uses it daily... going on 15(?) years old.